1. Field of the Invention
The present invention relates to a washing machine, and more particularly, to a dial knob installed at a control panel assembly of a washing machine so as to set a washing condition, and a manufacturing method thereof.
2. Discussion of the Related Art
In general, a washing machine is broadly classified into a pulsator-type washing machine with a vertically-installed drum, and a drum-type washing machine with a horizontally-installed drum.
In the drum-type washing machine, the laundry loaded into the drum is dropped and washed by the rotation of the drum.
Particularly, the drum-type washing machine has a control panel assembly installed at a front upper part thereof, for setting a washing condition and for displaying a washing state.
FIG. 1 illustrates a structure in which a dial knob is installed at the control panel assembly of the drum-type washing machine.
Referring to FIG. 1, a dial knob 10 is rotatably connected to a control panel assembly 15, and is used for inputting or selecting various washing conditions.
The dial knob 10 is attached on a center part or a side edge part of the control panel assembly 15.
The dial knob 10 includes a dial 11, a knob guard 12 and a plurality of lamp windows 13.
The dial 11 is rotated by a user, and is formed to have an about-cylindrical shape whose frond side is closed.
The knob guard 12 is ring-shaped and connected to the control panel assembly 15, and has a central opening through which the dial 11 is penetrated.
A plurality of window insertion holes 14 are formed on the knob guard 12.
A plurality of washing condition marks are printed on a surface of the control panel assembly 15 around a periphery of the knob guard 12.
The lamp windows 13 are respectively inserted into the window insertion holes 14.
A plurality of lamps (not shown) are respectively attached on rear surfaces of the lamp windows 13, whereby light rays of the lamps are respectively emitted through the lamp windows 13.
In the meantime, the knob guard 12 is manufactured by injection molding with an electroformed mold. A surface of the knob guard 12 is plated with metallic material. Here, the electroformed mold is a kind of a mold manufactured by electrolytically plating a pattern with nickel, copper, or the like, the pattern being made of glass, plastics, metal gypsum, wax, or the like so as to have the same shape as a molded article.
However, although it is possible for the knob guard 12 to be designed to have a simple metallic surface, it is difficult for the knob guard 12 to be designed to have a both lustrous and lusterless surface.